Quirks and Quarks - How feasting black holes time their burps

Episode Date: October 2, 2026

Black holes are voracious eaters, but they’re also quite messy, and often after devouring a star, they’ll let out a big burp, launching jets of high energy particles through space. Now, in a recent study, a team of astrophysicists has figured out the formula behind the timing of these burps. Also today: Skiing, hiking and roads are taking a toll on wolverinesThe buzzy, chirpy sounds of the Jurassic forestA notorious invasive species has been here a lot longer than we thought. Does that matter?Anomalies suggest King Tut’s tomb may conceal hidden chambersQuirks & Quarks has been nominated for a Signal Award! You can vote for us here. For more information about today’s episode, visit cbc.ca/quirks. 

One summer evening when she was 20 years old, something terrible happened to Vienna-Luc. I can't figure it out, but I do know that it was a violation. Then people started asking questions. What a creep. Who else knows about this? From CBC's personally, this is Agent Leila, the story of how a victim went undercover. So bring it on, let's go. Let's get a confession. Available now on CBC Listen, or wherever you get your podcasts. This is a CBC podcast.

Hi, I'm Bob McDonald. Welcome to Quirks and Quarks. On this week's show, tracking elusive wolverines in the mountains of Western Canada. And then we hung frozen beavers between trees, and that's enough to attract Wolverines. And figuring out why and when black holes burp. So we can just watch one star go in. The black hole will swallow the material, eject out some things. things and then at some point eventually we'll burp.

Plus, reconstructing the insect soundscape of the Jurassic, hints of hidden chambers in King Tutankhammon's tomb, and blurring the line between native and introduced species. All this today on Quarks and Quarks. Burping after a big meal is in many cultures considered to be quite rude, but you try telling that to a black hole. Black holes are voracious eaters. but they're also quite messy.

And after devouring a star, they'll often let out a big burp, launching jets of high-energy particles, tremendous distances through space. And while we humans might not want to be around for a huge post-dinner belch, astrophysicists often do want to see black holes spewing out this matter. But it's a big challenge for them to know when a burp is coming. Well, now in a recent study, a team of astrophysicists, including Dr. Adele Goodwin, has figured out the timing of these burps in the hopes of being able to catch them in action. Dr. Goodwin is with Curtin University in Australia.

Hello and welcome to our program. Hi, thanks so much for having me. First of all, describe a black hole burp. What's actually going on there? Yeah, so it sounds a bit strange to think that a black hole might be able to burp, but what we refer to them as are jets or outflows. And it's actually when the black hole is swallowing material, it forms an accretion disk, and that accretion disk can actually have very strong magnetic fields.

Particles can get channeled along those magnetic field lines and can get ejected out at really high speeds. And so this is what we would refer to as a burp, is this ejected material because we see it moving through the host galaxy of the black hole. Ah, so the accretion disk, that's the sort of a ring of material around the black hole before it falls in. Yeah, so as like material doesn't just fall in from all directions, it kind of forms a sort of flat structure that's swirling into the black hole. So kind of like how water swells down a bath pug, but it's gas swirling into a black hole. Well, we usually think of black holes as having voracious appetites that everything falls into a black hole, nothing gets out. So what's launching these jets? Yeah, this is, I think, quite a common misconception is that people always assume that black holes are these like,

giant sucking machines in space and that all this, like anything close to a black hole, will just be immediately swallowed. And that is true if it makes it within the event horizon, which is kind of like the point of no return for a black hole, where gravity is so strong that nothing can escape, not even light. But that's quite close to the black hole. And a lot of the interesting physics that happens around a black hole happens outside of the event horizon, in my opinion. And this is where we see these jets and outflows being launched from. Wow. It's sort of like, as you say, water going down to drain, it would be as though your bathtub is draining out, but some of the water is shooting up into the air. Yes, exactly. So, yeah, when you're watching water go down the bath, plug, it doesn't usually come out, but occasionally for a black hole, because there are magnetic fields and other things involved, particles can get really ejected out and at really high speed. So we're talking close to the speed of light sometimes, so highly relativistic ejections.

Wow. Well, how many of these black hole burps have been seen so far? We have seen probably on the order of 20 to 30 supermassive black holes burping after destroying a star. So the study that I published recently, we were looking at very specific types of black hole burps. So we were looking at what happens when one of these really big black holes destroys a star, just one star. And we watch it destroy the star and we watch it swallow that material. But it was really puzzling, and it puzzled us for a long time. Over the last sort of five to ten years, we've been watching more and more of these stars destroyed by black holes. And we've been seeing the burps happen at really random time.

So sometimes it would happen six months after the star was destroyed. Sometimes it would happen two or three years. And in one extreme case, it happened ten years after the black hole destroyed a star. Wow. So if these burps are kind of random or unpredictable, how did you go about trying to make sense of the timing of them? Yeah, so we started to ask the question, what is it that is producing these burps? We know from other types of black holes, so from the small black holes in our galaxy, or these really big black holes that are, you know, evolving on very long time scales.

We know that the thing that they're doing is they're swallowing material via this accretion it, so they're swirling gas in. And there is kind of a theory that at some point, this gas flow will reach a certain point and it will become slightly unstable, and that's when a bunch of material will be ejected out in a burp. And this critical point depends on the rate of the gas flow into the black hole. But that rate of the flow of the black hole is dependent on a lot of things. And so we did some really detailed modelling.

So the co-lead author of this study, Dr. Andrew Mammery from the Institute for Event Study in Princeton, we selected a sample of 20 of these black holes that had done burps, and he modelled it in really great detail. And I took the radio observation, so I was able to figure out, based on watching the radio observations, when the burps happened. And we were then able to match that together and figure out exactly at what rate the gas was going in when the burp happened. And it turned out that the rate was exactly the same across the population, even though the times went from six months to 10 years.

Okay, so take me through the process. If I could be close to a black hole without falling into it, and I'm watching it eat another star, when does it burp? Yeah, so, okay, the star comes in. It gets stretched into a long stream of material by the black hole's gravity or tidal forces, and it will kind of a bit of a messy process eventually form this disc. And initially the black hole is eating at a really high rate because there's a lot of gas at the start when, you know, you still got the whole star there.

And when it's eating at a really high rate, it actually is very messy and can eject out some material, which we call it a wind. It's not really a wind. So that happens initially. And then as it starts slowing down the rate that it's eating, when it gets to a very, very low rate, so there's only a little bit of gas left in the flow around the black hole, that's when this transition happens. and the flow sort of changes states

and a whole lot of gas gets ejected in a jet by kind of channeled along these magnetic fields. And so that is what we call the BIRB. So it happens at a very, very low flow rate, but it happens to be that that flow rate is the same across the population. It's just that some of the black holes started with a much higher eating rate than others

because they might have destroyed a bigger star, and that's why it could take much longer for them to get down to that rate. Why is it important to know that the fact that black holes burp and when they're going to do it? Being able to predict when a black hole is going to burp means that we can use a whole lot less telescope time. So if we don't know when a black hole is going to burp, we just kind of have to look at it every so often to try and catch the burp. But if we can predict, based on this model, when the black hole is going to burp, that narrows down a lot of the time that we have to use and we can really only only, we look at the ones that are going to birth.

But from a physics perspective, we don't actually understand the ejection mechanism. So, I mean, I said we think that there's magnetic fields involved. We think that perhaps even the spin of the black hole is important. But being able to say that the mass of the black hole is not important actually helps us learn about this jet ejection mechanism and the physics that's going on there. And that's kind of important because we know these jets. They're everywhere around the universe. They influence a lot of things.

They can influence the evolution of the host galaxies. But we don't really know exactly how or why they form. Dr. Goodman, thank you so much for your time. Thanks so much for having me. Dr. Adele Goodwin is a Forest Research Foundation Fellow at the International Center for Radio Astronomy Research at Curtin University in Australia. Maybe it's the power trying to come back on.

Movies like the 1993 Classes, Jurassic Jurassic Park have played a big role in shaping our imagination about what we think dinosaurs might have sounded like. But it largely remains a mystery because the soft tissues that make up the dinosaur's vocal tract rarely fossilize. So in the movie, sound artist created the roar of the T-Rex by combining tiger snarls, crocodile gurgles, and baby elephant screeches. But the nighttime scenes in these dino movies are still missing. something. Can you hear it? I'll give you a hint. Nowadays, insects like crickets transformed the night into a symphony of sound, and their sound-making parts often do fossilize.

And because of that, scientists have now been able to reconstruct some of the acoustic landscape from the Jurassic period. Dr. Fernando Montalegra Zapata led the study. He's a Canadian sensory biologist at the University of Lincoln in the UK, and he's going to give us a tour of this new audio landscape. Hello and welcome to our program. Thank you, Bob, for inviting me. So let's step into your Jurassic soundscape here and hear what it sounded like. So set the scene for me.

Where and when are we? Oh, that sounds like Inner Mongolia in China, 165 million years ago. Wow. In the Jurassic period. And yet it sounds so far. familiar to the sounds that we hear from insects today. What kind of insects are we listening to here? So we are listening here to ancient catedids, ancient Greeks, if you want to call it as well, or ancient crickets. So how similar or different were those ancestors? Did they look the same? What size were they?

Many of the species were larger than the ones we have now. Some species were starting to reduce body size. And so, in the The general mechanism has not changed that much. It's just the robbing of the wing together with one wind having very narrow file full of indentations. In the other wind will have an scraper. However, the strategies to radiate ultrasound in the living cadets, 70% of the species of the living cadence produced ultrasound has changed. The anatomy has changed. So the ancestors, they rub their wings together, one side is rough,

and sort of like a violin bow going across a string to make the sound? Exactly. That is the best description. Think of that as a nature's violin. Well, tell me about the different fossils that you worked with to recreate these sounds. So this goes back to 2012 when we recreated the first cold. there are two things that really fossilized in these fossils is the anatomy, the length of this tiny file scales with the frequency that will tell you which frequency the animal was using

and the anatomy of the file, the number of teeth will tell you the length of the duration of the basic syllable they produce. That's the only thing that really fossilized. So my colleague in Bristol say, I think that we can do much better. If we find more fossils with our colleagues in China, we can get better results. Oh, I see.

How many different fossils did you work with? For this recent research, we have 20 fossils organized in nine different species. I see. So what you did was you scanned these fossils, and then you made a computer model of them, and it was the computer model that you were able to manipulate and get your sound. Yes, we extracted the geometry in a two-dimensional model. because the fossils can be recovered only in two dimensions, these wings. And we extracted this into the computer.

And using information from some of the closest living ancestors of these Jurassic crickets, the material properties of the wing, the resonance, the behavior using laser-doppler barometry, and extract many other parameters and implement those in the fossils. Wow. So all of these values converge in a single frequency. Well, let's listen to your soundscape again. We'll just play a little bit of it here. Now, there's also a rhythm there.

Like, they're going, e, e, e, e, e, how did you figure that out? Each species will have a frequency and will have a rhythm to recognize each other. So what we did, we used artificial intelligence and machine learning. So training a model in which we include the rhythm of, many living species, the morphology, the anatomy, and the measurements of all of these living species, the temperature, how the temperature affects the rhythm in those species, because that has been studied many times. After training the model, we put all the fossils there, each one by one, and obtain a potential rhythm. We don't know if this was the real rhythm, but for sure,

we know that they were singing differently, each of them. Okay. So once you put all of this together and you played the sound of these Jurassic insects, what stood out to you about the sounds that they were making? People will say, oh, this is something very familiar to what we hear nowadays in a rainforest. Yeah, it might be at least the part that we can hear, of course,

because when you go to the rainforests to the Amazon, there will be a lot of sounds hidden there that you will not be able to hear in the wild. In the wild, about 165 million years ago. I mean, that's like you're traveling in time here. Exactly, yeah. Now, you mentioned that modern-day crickets and cadets can produce ultrasonic sounds. That's beyond our hearing range. Do you think the ancestors did the same thing?

Yes. I calculated the frequency first. The smaller files, 3.305, produced. tend to produce high frequencies and the larger files, low frequency when you, and that will give you a regression line of living animal. You put your fossil there. That particular species, Sigma Boilus Pellegrinus, gave us 21 kilohertz. And I said, this is ultrasound.

Humans can hear sounds up to 18, 20 kilohertz. We have three specimens of that species, three fossils, and we got frequencies between 22, 23, and 21 kilohertz. So that was definitely in the average was in the ultrasonic range. How much of a surprise was it for you that they were communicating in the ultrasonic range? I was surprised because people used to think, and actually myself, used to think that the ultrasound was produced just to avoid a predation of bats. Even though bats nowadays can hear the ultrasound,

ultrasound makes it difficult for a distant bat to detect a distant singer. But there were no bats around in the Jurassic period, were there? Yeah, there were no bats. 165 million years. Some of these animals were already exploiting the ultrasonic channels, and there were no bats there. Bats appear 100 millions later. Wow.

So the insects introduced ultrasonic communication. Yes, probably. Dr. Montalegro, thank you so much for your time. Thank you, Bob, for inviting me to Quicks and Quarks. Dr. Fernando Montalegra Zapata is a Canadian professor of sensory biology at the University of Lincoln in England. When I say the word Wolverine, what picture comes to mind? Is it the hairy Canadian superhero with razor-sharp metallic claws? You lost you money, you keep this, hope you lose something else.

Or do you picture the also hairy, weasel-like animal with its equally ferocious reputation? Now, we know relatively little about the wild wolverines that live in Canada, other than their numbers are lower than they used to be, and that they don't like to be around people. And they've been listed as a species of special concern here in Canada since 2014. But how humans affect their population numbers in places where we overlap has been a big unknown for the scientists who study them. A new, massive, multi-year study out this week attempts to answer that question. Dr. Miriam Barreto is a Wolverine researcher who led the study from the University of Calgary. Hello and welcome to our program.

Hello, Bob. Thanks for having me. Now, for anyone who may not be familiar with wolverines, just tell me a bit about them. What do they like? Where do they live? Wolverines are carnivores. They're 30 to 40 pounds. They're a big weasel. and they used to live throughout Canada, essentially everywhere. Wolverines now live mostly in the mountains, Boral Forest and the Tandra. And to describe them a little, they have really big feet, allows them to travel on the snow. They have thick fur.

They have huge home ranges, which they defend from each other. So each female has her own home range and each male has his own home range. And even though they're quite small, they have very, very slow reproduction. and that makes them a pretty unique species to live with. And what about their reputation for being vicious? How vicious are they? We used to think Wolverines were mostly scavengers, but I've learned since in the last 15 years

since I started working on them that they do hunt. And just last week I heard a story that's very credible, like I think the story is true of a Wolverine taking down a moose. A moose? A moose? A wolverine took down a moose. A moose, yeah, apparently. pin it against like a cliff and just stayed there for a week and attacked it for a week until mind you we don't know if the moose was maybe sick or old or something or injured right but still that's a massive animal and a small animal so they live in such a unforgiving landscape that

they do have to have a really big attitude right they encounter other large carnivores they encounter bears and and wolves and all sorts of other animals so they do have to be feisty smart and really like punch above their weight. But at the same time, they're pretty small and they do get killed by other animals. So I think the reputation is earned. There hasn't been a single known attack on humans. What are their numbers? I mean, how is the population doing? So we found that the population, there's still wolverines throughout the study area. And that area was big, 80,000 square kilometers, the size of Austria or twice the size of Switzerland. We found 300 Wolverines. And that's about half of what we expected just based on the habitat quality. Wow, 300 animals in 80,000 square

kilometers. Yeah, that's a pretty low number. So how did you study them if they're in the mountains and covering such a large area? We make them come to us. Yeah, you cannot, you cannot run after Wolverines. You have to essentially make them show up. Okay. How do you do that? So Wilreins are scam and trans hunters and we studied them in winter, mostly because then there's no bears around to make life hard for us. So we put out bait stations, we put up cameras and wooden contraptions that they have to climb to get in position for pictures. And then we hung frozen beavers between trees in front of the cameras. And we put a trapping lure out. And that's enough to attract Wolverines.

Okay. So you attract them to your bait. How do you gather data about them? When they climb our stations, we get photos of their chest, and they have unique fur patterns, like a tiger or a leopard. We can recognize the pattern and can identify them.

We also get pictures of their belly, so we can see if it's a male or female, and we can also see if the female is reproductive. And then also we collect hair samples for DNA analysis. The information where we see them, like at which stations we see them and how often, lets us calculate how many they are and also how many we missed. Now, you also wanted to find out about the impact of humans, so how did you incorporate that?

Essentially, we used, like, publicly available smartphone app data, those heat maps, like is also reflecting ski touring and hiking. And we knew from previous work that Wilrin's stay away from both hikers and skiers and snowmobiles too. We couldn't find a single data source that reflected exactly where people went, but we were able to use to calculate road density, which is just the density of logging roads and also paved roads in a given area. And that's a really good reflection for the disturbance from mechanized recreation,

such as snowmobiling and in summer, four-by-fouring and people on ATVs and quads. So once you put all of this together where the Wolverines are and where the people are, what did you see? We found that the impact of logging roads on females was pretty strong and the impact of recreation on females was not as strong yet. Why was the impact on females greater? Wolverines half are young in winter. They don't hibernate like bears. They're actually out and about in that time of year. So for half the year, females are really busy not only not only.

keeping themselves alive, but also somehow keeping their young alive in the years that they have young. So they just have additional business that the males don't have. So males mostly just worry about access to females in Wolverines. And they can stay away from people if they want to. But females, once they are in a specific, like once they have their young, they kind of tie to that area. And so they have to defend them from predators. And it seems like they probably assume that we are at danger to those young. So what's at stake if the Wolverines disappear? I guess what's their role in the environment?

I'm not sure we want to find out. Like, it seems to me many times where you take predators away and then suddenly there's more diseases or there's this or there's that or these other species suddenly explodes because you took away their predator. So I'm not necessarily sure I want to. know what happens once Wolverines or if Wolverines are gone. Dr. Barreto, thank you so much for your time. Thank you so much for being interested in Wolverines, Bob. Dr. Miriam Berretto is a Wolverine researcher who did the study at the University of Calgary. She's now a Lieber Arrow Fellow at the University of

Alberta. I'm Bob McDonald and you're listening to Quarks and Quarks on CBC Radio 1 and streaming live on the CBC News app. Just go to the local tab and press play wherever you all. Coming up later in the program, new clues in King Tutton Commons burial chamber may point to Queen Nefertiti's tomb. I've discovered the probability of at least five chambers to the north, all about the same size as King Tutton Commons tomb. One summer evening when she was 20 years old, something terrible happened to Vienna, Luke. I can't figure it out, but I do know that it was a violation. Then people started asking questions. What a creep.

Who else knows about this? From CBC's personally, this is Agent Leila. The story of how a victim went undercover. So bring it on. Let's go. Let's get a confession. Available now on CBC Listen, or wherever you get your podcasts. The Spiny Waterflee is a teeny tiny creature that has a giant impact. on our lakes. This microscopic predator is considered to be one of the most damaging aquatic invasive

species in North America. The voracious eaters, gobbling up zooplankton, which depletes food supplies, leads to the growth of algae blooms and costs over $100 million per lake to clean up. Researchers initially believed the spiny water flea was introduced to Canadian waters from European tankers in the 1980s. But a new study is completely turning that idea upside down. Aquatic ecologist Dr. Andrew Tannenzap used a mix of technologies, both old and new, to look at hundreds of spiny, water flea fossils found in mud cores from the bottom of Canadian lakes, and found that this nasty, invasive species has actually been living here for way longer than we'd thought. Dr. Tannenzap is a professor in the School of Environment at Trent University.

Hello and welcome to our program. Hi, Bob. Thanks for having me on. First of all, tell me about the spiny water flea. What's it like? The spiny water flea is this tiny but voracious predator. It's probably the size of your fingernail on your baby finger. And it really lives at the top of the food webs in lakes because it can escape predation by fish

because of the really long spined barb that it drags behind it. Think of it like a lion dragging a two by four. behind it. So that prevents fish from opening their mouths wide enough to ingest it. Oh, so nothing eats it, but it eats other other creatures. So what does it feast on? The spiny water flea loves other zooplankton. And these zooplankton grazers are really important. You can think of them as like tiny little lawnmowers that are grazing all of the algae that bloom inside of lakes. And so if we lose these lawnmowers, then What happens is that the algae can start to accumulate in the lakes and we can get reductions in water clarity, water quality, and all these knock-on effects on things like drinking water and all the cultural benefits that we derive from lakes.

Oh, I see. So the spiny water flea is the carnivore, the predator, and it eats the vegetarians that are eating the vegetation in the lake. Exactly. How widespread is it? So the spiny water flea is found throughout Eurasia. It's found in many kind of iconic lakes in Europe. And then it's spreading throughout northeastern North America, really well established in central and southern Ontario, several U.S. states.

And it's expanding into Quebec and into the maritime, we think. So do you know how it actually got here in the first place? Well, that's the great mystery. We don't actually know. So for about four decades, the accepted story had been that the spiny water flea came over from Europe in the ballast water of these transatlantic ships. It was first physically detected in Lake Ontario in 1982. And then the thinking has been that it's spread since then. But what's really interesting is that nobody has actually found the spiny water flea in ballast water coming over from Europe.

Wow. Well, what was your first indication that it's been here much longer than we thought? So our collaborators made a really amazing discovery in 2019. So sifting through the mud at the bottom of this lake in Muscoca, they discovered some fossils from the spiny water flea in mud that if we were to actually age that mud, it would come back to about 1650. So how could the spiny water flea end up deep inland in Ontario in the 1650s if the fossil that our colleagues found was accurate? There would have been no roads, there would have been no canals. How could it get so far inland? Well, take me through how you were able to trace the spiny water flea back so far in time. So the idea that we had was could we actually go and collect these fossils and date them directly? So measure the amount of radioactivity basically in these fossils to get an estimate of their age.

So this involved work in the lab with developing new methods, but it also required lots of spiny water flea fossils. So we went out to our study lake in Muscoca and we had to pull up about 30 to 40 sediment core. so these are collections of mud. So you can imagine trying to pull up something that weighs several kilos from a 13 meter depth and doing that 30, 40 times in a row. It was absolutely daunting. Okay, so once you got your sediment course from the bottom of the Muscoa Lake, what did you find when you got it into the lap?

So my PhD student had to sift through this mountain of mud to try and find enough spines. In the end, we needed about a hundred spines to actually pull them together and send them to the lab to get a date using radiocarbon technology. So what date did you come up with? So we discovered that this pool of spiny water flea fossils actually dated to before 1950. Now, part of the reason we can't come up with an exact age is because this is a pooled estimate, right, because we can't age a single fossil because they're too small. So the average age of our population was 1950, but that also means that there were individuals in there that were alive before 1950.

But 1950, I mean, that's not that long ago. What other data suggests that they've been there longer than that? So 1950 may not be as shocking as 1650, but it's quite significant for a number of reasons. The first being, there was no way really to get to these inland lakes in Muscoca before 1950 with transatlantic cargo ships. Now, on top of this complication, the Spiny Water Fleet really doesn't like being outside of water. It can't really survive for more than four hours outside of water.

So it's very unlikely that they would survive the transfer from one of these cargo ships into a smaller vessel and then make the journey up into the Great Lakes. and then they still had to find a way up to Muscoca when there were no canals and very limited road networks. Okay, so they didn't come from Europe, they didn't come up to St. Lawrence and through the Great Lakes. Dave, does this just suggest that the spiny water flea has been in the Muscoca lakes, the inland lakes forever?

They've always been there? Well, that's the next research question. So we don't really know the answer. The other thing I didn't mention is that we also have to be. had other lines of evidence that placed the spiny water flea in the Muskoka Lakes at least as far back as the late 1800s. And so the thinking is that maybe the spiny water flea has always been here and might even be everywhere. We just can't see it with the tools that we're using at the moment. So why is it important to know if it was introduced in the 80s or if it's been here for hundreds of

years. Why I think this is important is what if the spiny water flea is already everywhere and we just don't know. So we're spending a lot of money that is very limited and could potentially be used to control other species that we are much more confident that they've been introduced and have these detrimental impacts on the environment than the spiny water flea that might already be everywhere and it's just when noticing it now because it might be responding to environmental changes. So some of the effort on limiting the spread of the spiny water flea could be perhaps better allocated towards limiting increases in its abundance and the factors that promote its abundance, because if it's already everywhere,

why are we trying to control its spread? We should be trying to control its impacts. Dr. Tannenz out, thank you so much for your time. Thank you very much for having me on, Bob. Dr. Andrew Tannenzap is a professor and Canada research chair in climate change and northern ecosystems at Trent University. Now, the case of the spiny water flea does bring up an interesting question. How much does nativeness actually matter in an ecosystem? Countries around the world spend billions of dollars keeping a variety of introduced species at bay.

from small animals like the spiny water flea to big animals like wild pigs and many plant species like garlic mustard or dog strangling vine. We often feature interviews with researchers who are on the front lines combating these biological invaders. When it comes to our ecosystems, the prevailing idea is that native species are good and anything introduced is probably bad. But some scientists like Dr. Eric Lundgren are calling for a rethink on this idea. Because on our planet, where humans have altered almost every ecosystem through things like development, agriculture, and climate change, his research suggests that what matters isn't whether something is native or introduced, it's the role it plays within that ecosystem. Dr. Lundgren is an ecologist with the University of Alberta.

Hello and welcome back to Quarks and Quarks. Hey, Bob. Thanks for having me. Great to be back. First of all, can you explain how something like nativeness is measured in science? Yeah, it's a really interesting question. It's usually based on a certain moment in our history, generally relating to colonization, this moment in time when Europeans came to a place and started changing that place. And we tend to think of everything that was there before that moment as belonging and being native. and everything that's arrived since then as being introduced and not belonging. So as an ecologist, why does that topic interest you?

Because introduced species are everywhere. And, you know, I grew up thinking that they were all harmful and needed to be destroyed. And I spent a lot of energy in my youth killing garlic mustard and honeysuckle. And it was sort of a revelation to realize these organisms are here to stay. So what will they become? What does our future actually look like with these organisms? Well, where did this whole idea that introduced species are bad for an ecosystem? Where did that come from?

The historical roots of this concern are quite recent in a lot of ways. And they have grounding in certain patterns that are really remarkable of an introduced organism becoming extremely abundant and then having really strong impacts. We tend to think that native organisms have co-evolved with each other for millions of years into a sort of evolutionary harmony. and that introduced species disrupt that harmony. And this idea, it's plausible, but it actually lacks evidence. And so it remains something that's contested in the literature and in science. Well, tell me about your recent study looking at African megafauna. What did you find?

Just to give you some background on this, all the continents of our planet, including many of our big islands, used to have these rich assemblages of large animals. North America had camels and tapirs and several species of mammoth, and many species of horse. And these animals really exerted profound influences in reducing wildfire in keeping forests open and dispersing seeds. And yet, most of them went extinct.

So in North America, we lost most of our big animals 12,000 years ago. And yet, more recently, people have introduced big animals, wild pigs, wild horses, wild donkeys, just to name a few. And with these introduced organisms, we generally look at their impacts and we think that they're causing harm to ecosystems. So what we did in the study is we wanted to compare those effects to the effects of similar species where they're native,

including African megafauna communities, where those same impacts are considered valuable and natural. We see similar responses of plants and of small mammals and of soil to these processes, regardless of whether the animals are native or not. And so, you know, this African comparison really contextualized the fact that most of our modern ecosystems are missing a major component of herbivory, that we're dealing with these really simplified communities of animals. And that this irony of when these communities become more rich through introductions, instead of embracing that and studying it with curiosity,

we tend to reach for the gun or the poison. And so I think our work was important for pointing out the many of the claims about introduced organisms like wild horses in North America or wild pigs are actually not about their impact, but more about people not thinking those organisms belong because of a shallow idea of what is ecologically healthy. Well, yeah, I mean, here in North America, there's a lot of money being spent trying to manage introduced species, like mute swans, feral hogs.

What have you seen there? I think it's really fascinating how, you know, this metaphor of invasion really leads to a sort of simple response, a sort of knee-jerk response and we need to fight back because this is a hostile force that's coming to invade. And I think the metaphor really leads us astray,

whereas other ways of looking at ecosystems could include looking at the ultimate drivers of species abundance. So for instance, I've done some work on wild donkeys in the southwest, and you can have areas with tons of wild donkeys where they have really strong impacts.

And those areas tend to be places where mountain lions are absent. But if you go to places with mountain lions, you'll see the donkeys are very vigilant and their impacts are very different. And so instead of thinking about invaders in this sort of binary anthropomorphic logic, we should actually think about them as just members of ecological communities that are dynamic and responsive. And then instead of killing organisms or managing them intensively, perhaps we can redirect that funding towards addressing ultimate drivers. You know, and there's a plethora of these, including nutrient pollution and habitat loss and fragmental. and killing predators.

So you're saying that we should be looking at the function of the overall ecosystem rather than just the individual animals that are in it? Yeah, and it's akin to treating the medicine that treats a symptom instead of the cause. And I think a lot of what we call invasive species management is treating symptoms. I'm thinking about the example of zebra mussels in the Great Lakes. They came in on foreign ships. They're attaching to everything, clogging up pipes, and making the water in the large.

lakes clear, so the sunlight was going. I mean, there's a whole trickle-down, in fact, from these tiny little creatures. They cause a massive reorganization of the Great Lake ecosystems. I grew up on Lake Ontario, by the way, on the U.S. side, and zebra mussels were a big part of my childhood. I think that there's a lot of really interesting evidence about how all of that happened. Some of that evidence is that the lakes were so polluted that basically all the natives bivalves and such were declining, and the zebra muscles were pre-adapted to the type of environment we had produced through industry. And so the zebra muscle coming and cleaning the water of the lake,

it can be described as a harm or it can be described as the ecosystem actually being resilient and responsive and reorganizing with a new player that can actually fulfill a really important ecological role. One of the big complaints about introduced species is that they tend to outcompete the native species for food. What should be done about that?

I mean, that's possible. I've yet to see evidence of that in like empirical evidence that I've trusted. I think, again, it probably comes down to context. There are certain environments where some introduced organisms are going to be really, really successful and other environments where they're not going to be really successful. Which really comes down to this point,

which is if we were coming from outer space to planet Earth, could we come and figure out what species was native or not if we didn't already know? And this meta-analysis that we just published suggest that you couldn't. And many other meta-analyses that have looked at things like crabs and plants and pollinators also suggest that you can't tell

what organism is native or not if you don't already know. And so an example I just stumbled upon today is a coral that was described in the Caribbean. And so its native range was assumed to be the Caribbean. And then it shows up in Hawaii in the 1970s had never been detected before and it becomes super abundant in a few places, smothering native coral reefs.

And so everyone assumed it was invasive and introduced in Hawaii until someone did genetics on it and found out that actually it's native to the Pacific Ocean and probably native to Hawaii and it's actually introduced to the Caribbean, which highlights this unmeasurability,

unidentifiability of the native range. And so all those impacts that are used as justification for the eradication, all these lists of harms go from being harms to just normal parts of nature. And that's the really difficult thing with the word harm,

because we can call anything a harm. But every organism affects other organisms. That's how ecosystems work. That's what makes an ecosystem out of a list of species. And those effects are what regulate the system. These impacts when we think a species as native are valued, but when we think the species doesn't belong,

we call them harmful. Dr. Lundgren, thank you so much for your time. Thank you so much, Bob. Great to be here. Dr. Eric Lundgren is a postdoctoral researcher at the Center for Open Science and Research Synthesis at the University of Alberta in Edmonton. A little more than a hundred years ago, British archaeologist Howard Carter uncovered the entryway to what he suspected was King Tutankhamun's tomb. According to legend, he held up a candle to peer through a small hole he chiseled into a door and saw, wonderful. things. Golden chariots, ornate thrones, and furniture carved into the shapes of divine animals filled the tomb. But new geophysical data suggests a corridor and five or six other rooms may lie

beyond the chamber where King Tut lay buried. Could it be the final resting place of Queen Nefertiti, King Tut's stepmother who died about a decade before the young pharaoh? Previous geophysical investigations concluded there was nothing of interest beyond King Tut's Tomb, but a few years ago, a structural engineer who investigates historical constructions joined the team, and the results of his new work have just been published. George Ballard is the chairperson of the GBG group, a private company based out of the UK. Hello and welcome to our program. It's very good to meet you. Now, I've had the fortune of being to the Valley of the Kings, and I've been inside King Tut's tomb, and I was surprised how small it is.

It's tiny compared to some of the others in the valley. So once you joined the team, what was the physical evidence inside King Tut's tomb that showed you that there is possibly an entrance there? First physical evidence was the digitization of the decoration of King Tutankham's tomb. They digitized photographs of the various... scenes and they also included in that a topographic survey of the surface of the plasterwork. You can't touch the artwork. It's very, very fragile, but it gave you a sense in which you would almost feel the surface of the plasterwork and there were straight lines in it which formed the

shape of a doorway. Oh, I see. So it's sort of like the impression in the wall of a doorway. Yes. And that is immediately on the scene of a pharaoh performing the opening of the mouse ceremony, which allows the now dead, modified pharaoh to breathe and eat in the afterlife. The first version of that is an image of Queen Nefertiti with Tutankhaman opening her mouth and then it has been overpainted with an image of Tutin Carmen now in Mummy

with the new Pharaoh I opening his mouth. Wow. Why do you think the previous geophysical work was inconclusive after their investigation? There had been three geophysical surveys all spit up into little phases. The first one, Mr. Watanabe from Japan, who is famous in Japan, as an explorer and find through things with radar. He posited that there was possibly a chamber immediately beyond the North Wall.

Then National Geographic tried just radar and they concluded that there was no chamber behind the North Wall. And then the University of Turin came along and applied a considerable amount of both radar and resistivity measurements, which conclusively said we don't think there's a wall there. So once you arrived, what kind of technology did you have to investigate further what might lie beyond the tomb? Well, those three researchers were looking for avoided space, a room, and avoiding what I thought was wrong, which was trying to find a tomb, I looked at the structure, the North Hall,

to discover whether or not there was any structure within it, which happened to coincide with the information I already had, there was likely to be a blocked passageway. Every tomb in Egypt has the passageways to it blocked with rubble to prevent anybody from disturbing the dead or robbing them of the grave goods. And there are two ways you can look at this wall. The ground penetration radar, I use primarily short-range radar to look at the structure inside the tomb directly through the north wall itself.

And then I use the microgravity to extend beyond, which means as minute changes in the gravitational attraction of the Earth on the instrument, and spread out over a 35 meter by 35 meters square over the hillside above Tutankham's tomb. So you were looking down from above. You went outside the tomb onto the hill and we're looking down. How does this microgravity instrument work? Basically, it's a heavyweight, which is suspended on springs above the surface of the Earth. And as it moves up and down, according to the gravitational attraction on it,

we measure the amount of displacement of that mass. Oh, I see. So if there's an empty chamber, there will be less gravitational pull? Yep. Wow. So putting all of this together, paint me a picture of what you think lies beyond King Tut's North Wall too. Well, there's a lot of rock, but there are, I've discovered the probability of at least five chambers to the north, all about the same size as King Tut.

But the Valley of the Kings is created by floodwater, and every hundred years or so, There's a major flood running down the sides of the mountains above, and they tip over the cliffs into the valley, and those floods then rush through the valley, and that then risks. Any excavation at depth in the rock underneath the valley risks inundation. If I'm right that there is a large chamber at the northern end, then my suspicion is that it has probably already been damaged by floodwater,

then it is an urgent requirement to find out what we have got and whether or not we can still rescue anything before the next flood comes. Of the suspected chambers that are beyond King Tut's tomb, which one of them do you think could have nephrates sarcophagus in it? Logically, if this is a tomb that was prepared for nefertiti, during her lifetime, then the likelihood is that the large chambers that I'm proposing right at the end would be the place to bury her. However, there are also interesting variations in the density of each of the chambers that I have found. That could be due to collapse,

it could be due to them being full of artefacts, it could be due to them being full of artefacts, it could be due to people being interred there. We don't know, but we do have one which is really odd where there is a clearly defined chamber which has in its centre a very high density volume. That's as much as the gravity meter will tell me. Well, perhaps when the tomb is found, whoever does discover it will say,

I see wonderful things. That might be just the case, but just to see an anthropogenic chamber by one built by man would be, for me, wonderful things. Mr. Ballard, thank you so much for your time. And thank you indeed for giving me a chance to talk to you. George Ballard is the chairperson

of the Forensic structural inspection and investigation firm, GBG Group. And that's it for Quirx and Quarks this week. If you'd like to get in touch with us, our email is Quirx at cbc.ca. Our web page is cbc.ca. slash quarks, where you can check out our past episodes and find out more information about the research we covered in the show. You can also follow our podcast, get us on SiriusXM, or download the CBC Listen app. It's free from the App Store or Google Play. Quarks and Quarks is produced. by Sonia Biting, Rosie Fernandez, and Amanda Bukowitz.

Our senior producer is Hannah Hoag. I'm Bob McDonald. Thanks for listening. For more CBC podcasts, go to cbc.ca.ca slash podcasts.